Mary Fairchok

Two cases of Lactobacillus bacteremia during probiotic treatment of short gut syndrome.

Lactobacillus, a gram-positive bacillus, is a constituent of the indigenous flora of the colon. Often used as a probiotic agent, it appears to help prevent both intestinal colonization by pathogenic organisms and bacterial overgrowth syndrome. Lactobacillus organisms in the intestine are thought to produce acetic acid, lactic acid, and hydrogen peroxide and to promote the secretion of antimicrobial substances. The production of short chain fatty acids and the resultant low luminal pH of the colon also appear to inhibit growth of bacterial pathogens (1). Lactobacillus may also compete with pathogenic organisms for mucosal surface receptors and may decrease the incidence of antibiotic-associated diarrhea and Clostridium difficile colitis (2). Although Lactobacillus generally is not considered a pathogen, it can cause disease in compromised hosts, including bacterial endocarditis, pleuropulmonary infections, gastrointestinal abscesses, urinary tract infection, conjunctivitis, dental caries, and endometritis (3). Lactobacillus bacteremia, presumably secondary to bacterial translocation from the gastrointestinal tract, has been reported in a patient with severe intestinal inflammation caused by ulcerative colitis (4). There are no published reports of bacteremia or sepsis secondary to Lactobacillus given as a probiotic agent. We report two cases of Lactobacillus GG sepsis occurring during the therapeutic use of this organism.

FREQUENT AND PROLONGED SHEDDING OF BOCAVIRUS IN YOUNG CHILDREN ATTENDING DAYCARE

Abstract Background. Little is known about human bocavirus (HBoV) persistence and shedding and the association between HBoV detection and the onset and resolution of respiratory symptoms. Methods. We performed HBoV testing on nasal swab samples from a prospective, longitudinal study of respiratory illness in 119 children who attended daycare. Results. HBoV was detected in 70 children (59%) and in 106 (33%) of the 318 cases of illness. Another virus was detected in 76 (72%) of 106 HBoV-positive cases. Extended and intermittent shedding was observed, with consistent HBoV detection documented for up to 75 days. HBoV was detected in 20 (44%) of 45 asymptomatic enrollment samples, and HBoV prevalence and viral load did not differ significantly between children with and children without symptoms at enrollment. HBoV-positive illnesses were longer than HBoV-negative illnesses (odds ratio for duration of symptoms >7 days, 2.44; 95% confidence interval, 1.41–4.22), and illnesses with HBoV load ≥4 log10 copies/mL required a visit to a health care provider more often than did HBoV-negative illnesses (odds ratio, 1.64; 95% confidence interval, 1.02–2.64). Conclusion. HBoV was more common in illnesses with greater severity. However, detection of HBoV was not associated with the presence of respiratory illness or with specific respiratory symptoms in this prospective study of infants and toddlers attending daycare centers.

A comparison of 2 influenza vaccine schedules in 6- to 23-month-old children.

Background. Trivalent inactivated influenza vaccine (TIV) is recommended for all children ages 6 to 23 months. Delivering 2 doses of TIV at least 4 weeks apart to young children receiving this vaccine for the first time is challenging. Methods. We compared the immunogenicity and reactogenicity of the standard 2-dose regimen of TIV administered in the fall with an early schedule of a single spring dose followed by a fall dose of the same vaccine in healthy toddlers 6 to 23 months of age. Children were recruited in the spring to be randomized into either the standard or early schedule. An additional group was also enrolled in the fall as part of a nonrandomized standard comparison group. The 2002–2003 licensed TIV was administered in the spring; the fall 2003–2004 vaccine contained the same 3 antigenic components. Reactogenicity was assessed by parental diaries and telephone surveillance. Blood was obtained after the second dose of TIV for all children. The primary outcome measure was antibody response to influenza A/H1N1, A/H3N2, and B after 2 doses of vaccine, as determined by hemagglutination-inhibition titers ≥1:32 and geometric mean titer (GMT). Results. Two hundred nineteen children were randomized to receive either the standard or early TIV schedule; 40 additional children were enrolled in the fall in the nonrandomized standard group. Response rates in the combined standard versus early groups were similar overall: 78% (GMT: 48) vs 76% (GMT: 57) to H1N1, 89% (GMT: 115) vs 88% (GMT: 129) to H3N2, and 52% (GMT: 24) vs 60% (GMT: 28) to B. Reactogenicity after TIV in both groups of children was minimal and did not differ by dose, age, or time between doses. Reaction rates were higher in those receiving TIV and concomitant vaccines compared with those receiving TIV alone. Overall rates of fever >38°C axillary and injection-site pain, redness, or swelling were 5.4%, 3.1%, 0.9%, and 1.1%, respectively. Conclusions. When the spring and fall influenza vaccines had the same 3 antigenic components, the early vaccine schedule resulted in similar immunogenicity and reactogenicity compared with the standard schedule. When the vaccine components do not change between years, initiating influenza vaccine in the spring at the time of routine office visits would facilitate full immunization of children against influenza earlier in the season.

Epidemiology of viral respiratory tract infections in a prospective cohort of infants and toddlers attending daycare.

Abstract Background The epidemiology of respiratory tract infections (RTIs) in a daycare cohort has not been explored using molecular techniques. Objectives (1) Determine the overall incidence of RTIs in a daycare cohort using real-time reverse transcriptase polymerase chain reaction (RT-PCR). (2) Determine the relative incidence and impact of specific respiratory viruses, and characterize and compare clinical features associated with these pathogens. Study design In this prospective cohort study conducted from February 2006 to April 2008, nasal swabs were obtained from symptomatic children ages 0–30 months enrolled in fulltime daycare. RT-PCR was performed to detect respiratory syncytial virus (RSV), human metapneumovirus (MPV), influenza (Flu) viruses A and B, parainfluenza (PIV), adenovirus (AdV), human coronaviruses (CoV) and rhinovirus (RhV). Symptom diaries were completed for each illness. Results We followed 119 children (mean age 10 months; range 2–24 months) for 115 child years. The mean annual incidence of RTI per child was 4.2 the first year and 1.2 the second year of the study. At least 1 virus was identified in 67% RTIs. Co-infections were common (27% RTIs), with RhV, CoV, and AdV the most common co-pathogens. PIV was identified in 12% of RTIs with a high incidence of PIV4. The viruses with the greatest impact on our population were RSV, RhV and AdV. Conclusions Using molecular techniques, viruses were identified in approximately twice as many RTIs as previously reported in a daycare cohort. Infections with newly identified viruses, such as HMPV and CoV subtypes were less frequent and severe than infections with RSV, AdV and RhV.

Influenza Vaccine Immunogenicity in 6- to 23-Month-Old Children: Are Identical Antigens Necessary for Priming?

OBJECTIVES. Immunoprophylaxis with influenza vaccine is the primary method for reducing the effect of influenza on children, and inactivated influenza vaccine has been shown to be safe and effective in children. The Advisory Committee on Immunization Practices recommends that children 6 to 23 months of age who are receiving trivalent inactivated influenza vaccine for the first time be given 2 doses; however, delivering 2 doses of trivalent inactivated influenza vaccine ≥4 weeks apart each fall can be logistically challenging. We evaluated an alternate spring dosing schedule to assess whether a spring dose of trivalent inactivated influenza vaccine was capable of “priming” the immune response to a fall dose of trivalent inactivated influenza vaccine containing 2 different antigens. PATIENTS AND METHODS. Healthy children born between November 1, 2002, and December 31, 2003, were recruited in the spring and randomly assigned to either the alternate spring schedule or standard fall schedule. The 2003–2004 licensed trivalent inactivated influenza vaccine was administered in the spring; the fall 2004–2005 vaccine had the same A/H1N1 antigen but contained drifted A/H3N2 antigen and B antigen with a major change in strain lineage. Reactogenicity was assessed by parental diaries and telephone surveillance. Blood was obtained after the second dose of trivalent inactivated influenza vaccine for all of the children and after the first dose of trivalent inactivated influenza vaccine in the fall group. The primary outcome of this study was to demonstrate noninferiority of the antibody response after a spring-fall dosing schedule compared with the standard fall dosing schedule. Noninferiority was based on the proportion of subjects in each group achieving a hemagglutination-inhibition antibody titer of ≥1:32 after vaccination to 2 of the 3 antigens (H1N2, H3N2, and B) contained in the 2004–2005 vaccine. For each antigen, the antibody response was proposed to be noninferior if, within the upper bound of 95% confidence interval, there was <15% difference between the proportion of children in the fall and spring groups with postvaccination titers ≥1:32. RESULTS. A total of 468 children were randomly assigned to either the spring (n = 233) or fall (n = 235) trivalent inactivated influenza vaccine schedule. Excellent response rates to A/H1N1, as measured by antibody levels ≥1:32, were noted in both the spring (86%) and fall groups (93%). The A/H1N1 response rate of the spring group was noninferior to that of the fall group. Noninferiority of the spring schedule was not met with respect to the other 2 influenza antigens: for A/H3N2 the response was 70% in the spring group versus 83% for the fall group, and the response to B was 39% in the spring group versus 88% for the fall group. After 2 doses of vaccine, the geometric mean antibody titers also were less robust in the spring group for both A/H3N2 and B antigens. For each of the 3 vaccine antigens, the respective geometric mean antibody titers for the spring group versus the fall group were: A/H1N1, 79.5 ± 3.3 and 91.9 ± 2.6; A/H3N2, 57.1 ± 4.1 and 77.8 ± 3.7; and B, 18.0 ± 2.4 and 61.6 ± 2.5. However, a significantly higher proportion of children in the spring group achieved potentially protective levels of antibody to all 3 antigens after their first fall dose of trivalent inactivated influenza vaccine than children in the fall group after receiving their first fall dose. For influenza A/H1N1, there was an antibody level ≥1:32 in 86% of children in the spring group versus 55% of children in the fall group. Likewise, for influenza A/H3N2, 70% of children in the spring group and 47% of children in the fall group had antibody levels >1:32; for influenza B, the proportions were 39% of children in the spring group and 16% of children in the fall group. Reactogenicity after trivalent inactivated influenza vaccine in both groups of children was minimal and did not differ by dose. CONCLUSIONS. Although the immune response to the identical A/H1N1 vaccine antigen was similar in both groups, priming with different A/H3N2 antigens and B antigens in the spring produced a lower immune response to both antigens than that shown in children who received 2 doses of the same vaccine in the fall. However, ∼70% of children in the spring group had a protective response to the H3N2 antigen after 2 doses. Initiating influenza immunization in the spring was superior to 1 dose of trivalent inactivated influenza vaccine in the fall. The goal of delivering 2 doses of influenza vaccine a month apart to vaccine-naive children within the narrow flu vaccination season is a challenge not yet met; thus far, only about half of children aged 6 to 23 months of age are receiving influenza vaccine. By using the spring schedule, we were able to administer 2 doses of trivalent inactivated influenza vaccine to a higher proportion of children earlier in the influenza vaccination season. In years when there is an ample supply of trivalent inactivated influenza vaccine, and vaccine remains at the end of the season, priming influenza vaccine-naive infants with a spring dose will lead to the earlier protection of a higher proportion of infants in the fall. This strategy may be particularly advantageous when there is an early start to an influenza season as occurred in the fall of 2003. A priming dose of influenza vaccine in the spring may also offer other advantages. Many vaccine-naive children may miss the second dose of fall trivalent inactivated influenza vaccine because of vaccine shortages or for other reasons, such as the potential implementation of new antigens at a late date. Even with seasonal changes in influenza vaccine antigens, by giving a springtime dose of trivalent inactivated influenza vaccine, such children would be more protected against influenza than would children who were only able to receive 1 dose in the fall. In summary, our data suggest that identical influenza antigens are not necessary for priming vaccine-naive children and that innovative uses of influenza vaccine, such as a springtime dose of vaccine, could assist in earlier and more complete immunization of young children.

Epidemiology of Multiple Respiratory Viruses in Childcare Attendees

Abstract Background. The identification of multiple viruses during respiratory illness is increasing with advances in rapid molecular testing; however, the epidemiology of respiratory viral coinfections is not well known. Methods. In total, 225 childcare attendees were prospectively followed for up to 2 years. Nasal swabs were collected at respiratory illness onset and every 7–10 days until illness resolution. Swabs were tested by polymerase chain reaction for 15 respiratory viruses and subtypes. Results. At least 1 virus was detected in 382 (84%) of 455 new-onset illnesses with multiple viruses identified in 212 (46%). The proportion of subject swabs with multiple viruses detected changed as respiratory illnesses progressed from week to week, as did the prevalence of individual viruses. Children with multiple viruses detected at the time of illness onset had less frequent fever (odds ratio [OR], 0.56; 95% confidence interval [CI], 0.35, 0.90), however, these children more often had illness symptoms lasting over 7 days (OR, 1.94; 95% CI, 1.20, 3.14). Conclusions. A high proportion of daycare attendees had multiple viruses detected during respiratory illnesses. Delay between onset of illness and viral detection varied by virus, indicating that some viruses may be underrepresented in studies of virus epidemiology that rely on only a single test at symptom onset.

Severe morbidity and mortality with breast milk associated cytomegalovirus infection.

Congenital cytomegalovirus (CMV) infection can cause significant morbidity and mortality in the newborn period. Postnatally acquired CMV infection has been thought to carry much less morbidity. We report 5 cases of severe morbidity and mortality in very low birth weight infants with postnatally acquired, breast milk associated CMV infection.

Alternating Antipyretics: Antipyretic Efficacy of Acetaminophen Versus Acetaminophen Alternated With Ibuprofen in Children:

Methods A prospective, randomized double-blind placebo control study comparing the efficacy of acetaminophen to acetaminophen alternated with ibuprofen in 38 healthy outpatient children 6 months to 6 years presenting to the outpatient clinic with fever >38°C was conducted. Temperatures were recorded at 0, 3, 4, 5, and 6 hours. Side effect diaries and parental perception of efficacy were filled out hourly by parents. Results There were no significant differences in temperature between the 2 groups at times 0, 3, and 6 hours. The alternating group had significantly lower mean temperatures at both 4 hours (38.0°C vs 37.4°C; P = .05) and 5 hours (37.1°C vs 37.9°C; P = .0032). Parents did not perceive any difference in fever control between the groups. Conclusions An alternating regimen of acetaminophen with ibuprofen significantly decreased fever at 4 and 5 hours compared with acetaminophen alone. However, parents did not perceive a difference in efficacy.

Trivalent inactivated influenza vaccine (TIV) immunogenicity in children 6 through 23 months of age: Do children of all ages respond equally?

We assessed the effect of age on immunogenicity to trivalent inactivated influenza vaccine (TIV) by comparing the immune responses to influenza vaccine antigens among three age cohorts of vaccine-naïve children aged 6-11 months, 12-17 months, and 18-23 months. In children 6-23 months of age, antibody responses to TIV appear to increase with increasing age. Despite this finding, TIV was immunogenic even in the youngest age group evaluated, further establishing its value as a tool to protect young children from influenza. The role of age should be considered when assessing improved vaccines to enhance TIV immunogenicity and effectiveness in younger children.

Mupirocin Resistance Related to Increasing Mupirocin Use in Clinical Isolates of Methicillin-Resistant Staphylococcus aureus in a Pediatric Population

ABSTRACT We investigated the proportion of methicillin-resistant Staphylococcus aureus (MRSA) isolates from pediatric patients demonstrating mupirocin resistance related to mupirocin use at our institution. No mupirocin resistance was found in 98% of isolates, whereas mupirocin prescriptions increased by 110%. Resistance rates remained low despite the increasing use of mupirocin.